Light-operated switch



Nov. 30 1926.

L. 'ORTEGQ LIGHT OPERATED SWITCH Filed May 12. 1925 jEcz'g. 1.

ZJ 1 a a; 5. f v 5% afl m 5 5 Z m w Patented Nov. 30, 1926.

UNITE STATES LEO OB-TEGO, OF ALEXANDRIA, LOUISIANA.

LIGHT-OPERATED SWITCH.

Application filed May 12, 1925. Serial No. 29,750.

This invention relates to signal devices, and more particularly to means for utilizing the energy of light to open or close the contacts of an electrical circuit.

The primary object of the invention is to provide means for operatively associating a light absorbing thermostat with an electrical switch, whereby, under the dilierential infiuence of light and darkness, the thermostat will be expanded or contracted to automatically open or close the switch, and thus control a signal light or other device to wh ch the switch is connected.

A "further object of the invention consists in the provision of a simple and inexpensive light operating apparatus which will "function efficiently under varying degrees of light and darkness, and will not be n'iaterially influenced by atmospheric changes.

Referring to the drawings, wherein is set forth a preferred embodiment of the invention:

Figure 1 is a vertical sectional view of the apparatus, and

Figure 2 is a sectional view taken sub stantially along the line 22 of Figure 1.

Referring to the drawings, in which like numerals indicate like parts in the several views, 10 denotes a base made of any suit able insulating material, which is provided on its upper surface with an annular groove for the reception of the beaded end 11 of a transparent glass casing 12. A metallic circular band or ring 13, mounted on the base 10 adjacent the outer edge thereof, has a series of upwardly extending rods 14 which converge at a point above the casing 12 and act as a guard for the same. The base 10 and the metallic band 13 have a plurality of spaced openings 15 which receive retaining means for securing the apparatus to a suitable support (not shown).

The base 10 is preferably provided with a recess 16 in the underside thereof, through which extend the conducting wires 17 and 18 that are connected to the contact members 19 and-20 by the binding posts 21 and the nuts 22. The contact member 19 has a bifurcated end 23, in which is movably mounted a switch bar 24 by the transverse pin 25. The switch bar 24 is preferably weighted at one end, as at 26, so that this end will normally engage with the contact member 20 to close the circuit. The contact member 20 is further provided with an ad justable screw 27 which engages the underside of the switch 24 to limit the movement of the latter. A substantially U-shaped support 28 mounted on the base 10 by the bolts 29, has a central boss 30 which receives the shank 30 of a thermostat 31. The thermostat 31 is preferably composed of a metallic disk Formed so as to expand when heated and contact when cool. Additionally, the surface of the thermostat is coated with lamp black or the like to make it lightabsorbing. Depending centrally from the underside of the thermostat 31 and in direct alignment with the end of the switch bar 2a is a plunger rod 33, arranged, when the thermostat is expanded, to depress the end of the switch bar, which, in turn, raises its opposite end 26, thus breaking the circuit between the contact members 19 and 20.

The thermostat 31 is hermetically enclosed within the casing 12 by reason of the fact that the annular bead 11 is secured to the base 10 by any suitable sealing material 34, which forms an airtight joint between the parts. The binding posts 21 are likewise extended through an enlarged recess in the base 10, which is filled with sealing wax 35 so as to exclude air from entering the interior of the casing. The thermostat 31 may be adjusted vertically relative to its support 28 by means of a set screw 36 which engages the shank 30 for maintaining the latter in fixed position. Due to the weighted end 26 of the lever 24 normally tending to maintain the circuit closed, it will be observed that in the event of the thermostat failing to function the signal will remain on.

While the invention is particularly adapted for use with railroad, maritime and aeronautical signal devices to automatically light a bulb and give a warning at night or in foggy and cloudy weather, it may equally be employed for various other purposes to efiect a saving in the consummation of electricity and increase the longevity of parts that wear quickly under constant usage. Furthermore, instead of enclosing the thermostat in an airtight container, it is obvious that the same may be installed in a vacuum bulb or the like.

The operation of the device is as follows:

Assuming the device to be in a position where it will function under the varying degrees of light and darkness, it will be seen that when the thermostat 31 is con tracted, as shown in Figure 1, the circuit is closed, due to the weighted end 26 of the switch bar engaging the contact member 20. As the rays of light from the sun strike upon the surface of the thermostat 31, these rays are converted into heat which expand the thermostat and the air within the same, causing the plunger 33 to depress the adjacent end of the switch bar 24, and thus break the circuit between the contacts 19 and 20. When it becomes cloudy or darkness approaches, the thermostat will contract,causing the Weighted end 26 of the switch bar to again engage the contact member 20, and thus close the circuit.

The device is arranged to be responsive to the ditferential influence of light and darl ness at all times, due to the fact that the end of the switch bar 2% may be adjusted relative to the plunger 33 by movement of the set screw 2'7. Additionally, the metallic parts within the casing 12 may be coated with lamp black or the like to assist in drawing the rays oi. light to the casing.

It will be understood that the form of the invention shown and described is merely illustrative, and in no sense restrictive, and that such changes as fall within the purview of one skilled in the art may be made without departing from the spirit of the invention and the scope of the appended claim.

I claim:

In combination, a switch operable under the differential influence of light and darkness, comprising a base having a recess in the under side thereof, a pair of electric con tact members mounted on said base, conducting wires extending into said recess and connected to said contact members, a switch bar pivoted to one of the contact members and having a weighted end for causing the same to normally engage the other contact mem her for closing the circuit, means on the last mentioned contact member for adjusting the swinging movement of the switch bar, a substantially U-shaped support secured to said base, a metallic thermostat having a light absorbing surface suspended from the horizontal arm of said support above said switch bar and adapted to expand and contract under the differential influence of sunlight and darkness, said thermostat having a d pending arm aligning with one end of the switch bar and arranged when expanded by the thermostat to depress the switch car and break the circuit between the contact members, and a transparent casing mounted on said base and hermetically enclosing the thermostat therein.

In testimony whereof I have hereunto set my hand.

LEO ORTEGO. 

